Adaptive receiver

Abstract

A nonlinear control system and a speaker protection system are disclosed. In particular, a control system for adapting an audio output from a speaker in the proximity of an object is disclosed. The controller is configured to accept one or more input signals, and one or more estimated states produced by the model to produce one or more control signals. A speaker protection system and a quality control system are disclosed. More particularly, a system for clamping the input to a speaker dependent upon an estimate of the proximity, acoustic volume, and/or acoustic coupling of the speaker to a nearby object is disclosed.

1 .- 26 . (canceled) 
     
     
         27 . An audio system for generating a signal indicative of the proximity of a speaker from an ear of a user, the audio system comprising:
 an input for receiving one or more input signals, wherein at least one of the input signals comprises a diagnostic signal;   an output for outputting an output signal to the speaker, wherein the output signal is based on the one or more input signals; and   an estimator for receiving, from a microphone located facing the speaker, a feedback signal based on the output signal, wherein the estimator generates the signal indicative of the proximity of the speaker from an ear of a user based on the diagnostic signal.   
     
     
         28 . (canceled) 
     
     
         29 . A system for determining a proximity state relating to a proximity of a speaker to an object, the system comprising:
 an input configured to receive a feedback signal generated by a feedback microphone located between the speaker and the object, wherein the feedback signal is influenced by the proximity of the speaker to the object; and   proximity estimating circuitry configured to:   assess a coupling between the speaker and the feedback microphone using a feedback algorithm, and   generate a proximity state reflective of the proximity of the speaker to the object based on the feedback signal and the coupling.   
     
     
         30 . A system for determining an extent of a gasket between a speaker to an ear of a user, the system comprising:
 an input configured to receive a feedback signal generated by a feedback microphone located between the speaker and the ear of the user, wherein the feedback signal is influenced by a proximity of the speaker to the ear of the user; and   proximity estimating circuitry configured to:   use the feedback signal and frequency sensitivity measurements to detect an extent of a gasket between the speaker and the ear of the user.   
     
     
         31 . A system for determining an extent of a gasket between a speaker to an ear of a user, the system comprising:
 an audio path configured to deliver an audio signal to the speaker;   an input configured to receive a feedback signal generated by a feedback microphone located between the speaker and the ear of the user, wherein the feedback signal is influenced by a proximity of the speaker to the ear of the user; and   proximity estimating circuitry configured to determine a proximity state based on the feedback signal, wherein:   the system is configured to clamp the audio signal or restore the audio signal based on whether the proximity state indicates establishment or loss of a gasket between the speaker and the ear of the user.   
     
     
         32 . A proximity detector, comprising:
 an input configured to receive an audio signal generated by a microphone configured to sample an output of a speaker; and   a processor configured to determine a characteristic of the audio signal and determine a proximity of the speaker to an object based on an analysis of the characteristic.   
     
     
         33 . The proximity detector of  claim 32 , wherein the microphone is a feedback microphone. 
     
     
         34 .- 35 . (canceled) 
     
     
         36 . The proximity detector of  claim 32 , wherein the characteristic comprises a response of the audio signal at a particular frequency and under a known condition. 
     
     
         37 . The proximity detector of  claim 32 , wherein the audio signal comprises a diagnostic audio stream mixed with other audio content. 
     
     
         38 . The proximity detector of  claim 32 , wherein the characteristic comprises an energy of the audio signal. 
     
     
         39 . The proximity detector of  claim 32 , wherein the characteristic comprises an energy of a portion of the audio signal. 
     
     
         40 . The proximity detector of  claim 32 , further comprising a filter configured to filter a portion of the audio signal prior to processing of the audio signal by the processor to determine the characteristic. 
     
     
         41 . The proximity detector of  claim 32 , wherein the processor is further configured to generate an output signal for causing an event based on determining the characteristic of the audio signal. 
     
     
         42 . The proximity detector of  claim 41 , wherein the event is a change in a power associated with the speaker. 
     
     
         43 . The proximity detector of  claim 41 , wherein the event is a cessation of a playback signal driving the speaker. 
     
     
         44 . The proximity detector of  claim 41 , wherein the event is a start of a playback signal driving the speaker. 
     
     
         45 . A method, comprising:
 receiving an audio signal generated by a microphone configured to sample an output of a speaker; and   determining a characteristic of the audio signal; and   determining a proximity of the speaker to an object based on an analysis of the characteristic.   
     
     
         46 . The method of  claim 45 , wherein the microphone is a feedback microphone. 
     
     
         47 .- 48 . (canceled) 
     
     
         49 . The method of  claim 45 , wherein the characteristic comprises a response of the audio signal at a particular frequency and under a known condition. 
     
     
         50 . The method of  claim 45 , wherein the audio signal comprises a diagnostic audio stream mixed with other audio content. 
     
     
         51 . The method of  claim 45 , wherein the characteristic comprises an energy of the audio signal. 
     
     
         52 . The method of  claim 45 , wherein the characteristic comprises an energy of a portion of the audio signal. 
     
     
         53 . The method of  claim 45 , further comprising filtering a portion of the audio signal prior to processing of the audio signal by the processor to determine the characteristic. 
     
     
         54 . The method of  claim 45 , further comprising generating an output signal for causing an event based on determining the characteristic of the audio signal. 
     
     
         55 . The method of  claim 54 , wherein the event is a change in a power associated with the speaker. 
     
     
         56 . The method of  claim 54 , wherein the event is a cessation of a playback signal driving the speaker. 
     
     
         57 . The method of  claim 54 , wherein the event is a start of a playback signal driving the speaker.